Plug socket



Sept, 10, 1935.

J. W. VAN NOORDEN PLUG SOCKET Filed March 11, 1955 Patented Sept. .10, 1935 UNITED STATES PATENT OFFICE PLUG SOCKET Jan Willem van Noorden, The Hague, Netherlands Application March 11, 1935, Serial No. 10,574 In the Netherlands February 23, 1934 2 Claims.

5 with plug sockets are to be provided with solid pins and consequently the said sockets must needs comprise resilient contact members for receiving the pins.

Several constructions for plug sockets of this kind have been proposed already, but they have the disadvantage that they do not provide a good contact surface between the pins and the contact members in the socket, which may cause overheating of the contact surfaces, formation of sparks at the points of contact and will not always guarantee absolute safety of operation. An-

' other disadvantage is that on account of the insuflicient friction between the pins and the contact members in the socket, the contact plug may I be too readily withdrawn from the socket. Moreover, the greater part of the known plug sockets are not suitable for use with contact pins of different cross sections. In these constructions the action of the spring has always been exerted in a direction perpendicular to that in which the plug pins were inserted into the socket, which never produced satisfactory results.

The invention has for its purpose to provide a socket which does not possess the above mentioned disadvantages, which can be manufactured at a very small expense and which can be easily mounted in an insulating member. Moreover the construction according to the invention complies with all the provisions of safety boards and similar institutions, which hitherto has not been the case with any of the known devices of this nature.

According to the invention the socket proper comprises one or more contact members which members together form a cylindrical sleeve for the contact pin, and which are pressed towards each other under the action of a spring, and after the insertion of the pin always remain absolutely parallel to each other.

According to the invention the contact members are enclosed in a casing which has an opening at the top for inserting the pin, the edges of the said opening being conical with the angle of inclination corresponding to that of the conical end surfaces of the contact members, whilst a spring is provided inside the casing acting from below against the bottom part of the contact members. There also may be provided below the contact members a member with a conical surface which is pressed by means of the said spring against the bottom part of the contact members, which in that case are each provided with a corresponding conical edge.

The accompanying drawing shows an embodi- 5 ment of the invention according to the latter constructions.

Fig. 1 represents a contact casing with associated parts, to be used in a plug socket according to the invention, at the moment of inserting the 10 contact pin.

Fig. 2 is the same casing after the contact pin has been completely inserted.

The contact casing comprises a casing i, having a cylindrical inner surface and an opening at the top for inserting a cylindrical contact pin 2. The inner edge of the opening in the casing I presents a conical surface and this conical surface 3 gradually merges into the cylindrical inner surface.

The lower part of the casing l is provided with interior screw threads 6 for screwing in a plug 5 which may contain, for example, a terminal 6.

In the casing l a spring 1 is provided supporting a bowl-shaped member 8 slidingly fitted into the casing and having at its upper end a downwardly inclined conical surface 9. Between the conical surface 3 and the conical surface 9 there are provided two approximately semi-cylindrical contact members HG, i l, the upper and lower edges of which have conical surfaces l2 and i3 respectively, the angle of inclination of which correponds to that of the surfaces 3 and 8.

When the contact pin 2 is being inserted, the contact members it and ii, together with the bowl 8 will be first moved downwardly a little, against the action of the spring l, which will allow them to move apart so far that the pin 2 may be inserted into the opening between the same. At first the contact members iii and l i which are 40 supported by the conical surface 9, will take an inclined position with regard toeach other, as indicated in Fig. 1. When the pin 2 is inserted further (vide Figure 2) the contact members Ill and. l i will again be located parallel to each other and against the cylindrical surface of the pin 2, as the conical surfaces It will move upwardly along the conical surface 9.

It is evident from the above that under all circumstances the contact members will provide a large contact surface with the contact pin and that on account of this large contact surface the friction between the contacting members and the contact pinwill be sufficiently great. Even when a contact pin of a smaller cross section is action exerted on the contact members by the conical surfaces 3 and 9.

I claim:

1. In an electrical socket, a hollow casing having an entrance for the insertion of a pin and a bevelled inner surface adjacent said entrance. a sliding member within said casing having a complementary bevelled surface facing said entrance, a plurality of contact members between said bevelled surfaces forming a group with opposed contact faces to receive the pin and having bevelled ends cooperating with said bevelled surfaces, and a spring in said casing pressing said sliding member against said contact members and said contact members into gripping relation. 5

2. An electrical socket as described in claim 1, wherein said casing has a cylindrical interior and said sliding member is in the form of a cylindrical block slidably fitting in said casing and having a cup-shaped conical surface facing said entrance. 10

JAN WILLEM VAN NOORDEN. 

